Cut through fiberglass hull

[smhekma]

So I messed up here... I was removing the rotted out floor and in this spot upfront I hit a thin spot beyond the floor and poked through and made about an 8" gash through the hull. I was using an oscillating Dremel blade so it's pretty thin, but just wanted some second opinions for repairing. I was hoping to do the bulk of the repair from the inside using fiberglass (w epoxy resin). On the outside of the hull I was hoping I could do as little as possible and just hit it with some tinted epoxy. Not sure if something like this really needs a double sided repair where I should actually also add fiberglass to the outside as well.

 

[matt167]

grind the gelcoat down to fresh glass, grind it down to fresh glass on the inside, and build a patch on both sides with 1708. Sand fair and done

 

[racerone]

Lots of room on the inside for hefty ( 3 layers ) structural repair.----Go 6" above and 6" below the cut.-----Cosmetic fix on the outside.------In rough water and waves you do not want any flexing there.

 

[sms986]

I did this on mine. I ground a dime size hole in the hull. Rub some painter's tape on your jeans then tape up the outside of the hull pretty well before glassing. This will keep the resin from dribbling down the outside and rubbing it on your pants first makes it easy to peel off. Made a nice flush repair on the outside.

 

[tpenfield]

Nice work . . . it happens.

You'l want to grind a bit away around the cut and patch it on both sides. Fill the actual cut with peanut butter mix.

 

[smhekma]

Well so far seems like I am getting recommendations for both ways... lol. I would add this is a 15.5 ft boat, with 40hp motor that is exclusively being used on smaller Northern MN lakes. Just calling that out as this isn't a high speed boat being used on in really rough waters. My hope since I have all the room in the world on the inside was to do a heavy structural fiberglass repair there, but keep it to some minimal sanding and epoxying on the outside.

 

[gm280]

OMG, you cut totally through the hull. Well that boat is now trash... lol

If I had a $100 dollar bill for everyone on these forums that did that exact same thing, I could buy me a brand new boat...well at least a small new boat.

Don't worry, seems everyone, doing such a refurbishing, accidently cuts through the hull. I probably only did it about three or four times myself. But I would certainly grind to fresh fiberglass on both sides and layer at least 6" around all sides or the cut and apply 1708, as stated above. You will see that once you start feathering the 1708 in, it gets really smooth pretty quick. Especially if you apply some "peanut butter" mixture over the 1708. Then use what ever outside color paint or gelcoat and move on.

Peanut butter is a mixture of Polyester Resin, Cabosil (Fumed Silica) and even some CSM (chop strand fiberglass, usually 1/4" size) until you get a peanut butter consistency and apply that. Of course you also have to mix in the proper amount of MEKP (Methyl Ethyl Ketone Peroxide it comes with the Polyester Resin) hardener for the amount of Polyester Resin you use. It feathers very nicely , and pretty easy to sand as well. JMHO

 

[Scott Danforth]

I drilled a few holes in my boat this last go-around as well...... Ship happens.

 

[Grub54891]

Shoot, it happens. One boat I had, the po screwed a new deck on. Yeah the boat was rotten. One drywall screw was through the hull. I found it and just filled the hole with epoxy. Now she's getting a full re-hab.